1. Field of the Invention
The invention relates to a terminal component and a method of manufacturing the terminal component, and more particularly, to a terminal component having an internal terminal and an external terminal joined to each other, and a method of manufacturing the terminal component.
2. Description of Related Art
Terminal portions of a battery or the like are often joined to each other through laser welding in order to ensure conduction of the terminal portions. However, the cost required for laser welding is high. Therefore, it has been considered to join the terminal portions to each other with the aid of adhesion joining such as caulking or the like.
As for the aforementioned art, Japanese Patent Application Publication No. 2013-161629 (JP 2013-161629 A) discloses a method of manufacturing a secondary battery that is equipped with an electrode body, a case that accommodates the electrode body, an external terminal that is provided so as to protrude outward of the case, a collector terminal that connects the electrode body and the external terminal to each other, and a gasket that is interposed between the collector terminal and the case. The method of manufacturing the secondary battery according to Japanese Patent Application Publication No. 2013-161629 (JP 2013-161629 A) includes a process of protruding part of the collector terminal outward of the case in such a manner as to pass through part of the external terminal, subjecting a protrusion portion of the collector terminal to caulking to apply a compressive force to the gasket, pressing a caulking portion formed through this caulking while applying heat thereto, and joining the caulking portion and the external terminal to each other.
A water droplet may adhere to the surface of the battery due to condensation or the like. However, with the manufacturing method according to Japanese Patent Application Publication No. 2013-161629 (JP 2013-161629 A), a water droplet may enter a gap between the external terminal and the internal terminal (the collector terminal) that are joined to each other. Then, the joint portion of the external terminal and the internal terminal may corrode due to the entrance of a water droplet into the gap. Furthermore, the conduction resistance (electric resistance) between the external terminal and the internal terminal may rise due to corrosion of the joint portion.